1. Field of the Invention
The subject invention relates to a security apparatus for an electronic device and a method of determining the distance between a first electronic device and a second electronic device for allowing a user access to one of the first and the second electronic devices.
2. Description of the Prior Art
The prior art includes various security apparatuses and methods of determining the distance or proximity between a first electronic device and a second electronic device. The methods include the steps of emitting. a radio frequency (RF) signal and an audio signal simultaneously from the first electronic device, detecting the RF signal and the audio signal with the second electronic device, and measuring a time interval between the detection of the RF signal and detection of the audio signal by the second electronic device.
One such method is shown in U.S. Pat. No. 6,009,358 to Angott et al. The ""358 Patent discloses using radio frequency (RF) signals and audio signals to determine the position of a lawnmower in a plot of land. The lawnmower position is determined and then the position is corrected to a memorized route which the lawnmower is programmed to follow. If the route was not preprogrammed into the lawnmower, the position of the lawnmower would not be corrected and no response would be taken.
Another similar method is shown in U.S. Pat. No. 5,821,854 to Dorinski et al. The method utilizes radio frequency (RF) signals to determine the proximity of a user to a computer. When the strength of the RF signal falls below a predetermined threshold, an inaudible sound is emitted and the computer locks when it detects the inaudible sound.
Note that none of the prior art references enable or disable the device in response to the position of the device. Accordingly, there is a need for an apparatus and a method which determines the proximity of the user within a predetermined time range or radius and enables and disables the device to protect valuable information that is increasingly being stored on electronic devices and decrease the likelihood of information theft.
The subject invention provides a security apparatus and a method of determining the distance between a first electronic device and a second electronic device for allowing a user to access one of the first and the second electronic devices. The apparatus comprises a first electronic device and a second electronic device. The first electronic device includes a first transceiver connected to the first electronic device and having at least one antenna for emitting and detecting a radio frequency (RF) signal, a first detector connected to the first electronic device for detecting an audio signal, and a counter connected to the first electronic device for measuring a time interval between a transmitted RF signal and audio signal from the second electronic device. The second electronic device includes a second transceiver connected to the second device and having at least one antenna for emitting and detecting a RF signal, a transmitter connected to the second electronic device for emitting an audio signal.
The apparatus is characterized by a first processor connected to the first electronic device for comparing the measured time interval to a predetermined time range and enabling one of the first and second electronic devices in response to the time interval being within the predetermined time range and disabling one of the first and second electronic devices in response to the time interval being outside the predetermined time range.
The method comprises the steps of emitting a radio frequency (RF) signal and an audio signal simultaneously from the second electronic device, detecting the RF signal and audio signal with the first electronic device, and measuring a time interval between the detection of the RF signal and detection of the audio signal by the second electronic device.
The method is characterized by comparing the measured time interval to a predetermined time range and enabling one of the first and the second electronic devices in response to the time interval being within the predetermined time range such that the user may have access to the enabled electronic device and disabling one of the first and the second electronic devices in response to the time interval being outside the predetermined time range such that the user cannot have access to the disabled electronic device.
The subject invention provides for a more secure electronic system by determining the proximity of the user from the electronic device and disabling the electronic device to prevent information theft when the user is outside of a predetermined radius.